Growth of Muslim Population in Medieval India (1000-1800) is a book written by K. S. Lal published in 1973.

The book assesses the demographics of India between 1000 CE and 1500 CE. On the basis of the available historical evidence, K.S. Lal concluded that the population of Indian subcontinent in 1000 was about 200 million and in 1500 was about 170 million. He says, however, that "any study of the population of the pre-census times can be based only on estimates, and estimates by their very nature tend to be tentative."

Lal estimates that about 60 to 80 million people died in India between 1000 and 1525 as a result of the Islamic invasion of Indian subcontinent. He concluded that about 2 million people died during Mahmud of Ghazni's invasions of India alone.[1]

Stephen Neill in his book A History of Christianity in India: The Beginnings to AD 1707, regarded the statistics and material to be "Important sidelights".[2] Simon Digby disputed Lal's study of the demographic situation in medieval India in a review in Bulletin of the School of Oriental and African Studies, Digby suggested that estimate lacks accurate data in pre-census times.[3] Historian Irfan Habib criticized the book in his "Economic History of the Delhi Sultanate - An Essay in Interpretation" (Habib 1978). K. S. Lal wrote a reply to Irfan Habib's criticism in 1979 (Lal 1979) and in 1999 (Lal 1999).

Koenraad Elst refers to Lal's statistics in his book Negationism in India: Concealing the Record of Islam, remarking that "More research is needed before we can settle for a quantitatively accurate evaluation of Muslim rule in India, but at least we know for sure that the term crime against humanity is not exaggerated."[4]

Recently, historian Jeremy Black in his book Contesting History: Narratives of Public History (2014), remarked these writings to be "recent good works".[5]